Integrated cooker isolator not isolating power...help!

[Tom M]

I’ve recently purchased and moved into my first home (3 weeks ago). The property  has an integrated electric Lamona cooker (oven and hob), which was present prior to our ownership. During conveyancing, all satisfactory electrical certificates were supplied.

Today, I noticed the isolator power switch does not isolate power to the appliance; the only way to turn it “off” is to set the oven and hobs to an off setting themselves. I’m sure the isolator switch has worked previously since we moved in, although I cannot be 100% sure, as I always set the oven and hob settings to off, as well using the isolator switch, to power off.

Does anyone know what is likely to be the cause for this and a solution? I have not attempted to remove the isolator cover or cooker to inspect further yet, but I cannot see another place the cooker is plugged into for a power source. For background, I’m not an electrician by any stretch of the imagination!

Thanks for the help in advance.

 

[roys]

If you switch the cooker circuit breaker off at the consumer unit (fuse board) what happens, does the power to the hob, oven, or both go off now?

 

[Evans Electric]

The switch may be connected incorrectly  so that it,s not actually breaking the circuit .

Or it may be a redundant switch with the real cooker switch in a cupboard .  

Can you take a look underneath & in the cupboards ...look for a thick cable between the  isolator & the cooker.  

The oven bit may have a 13A  plug & lead  , and may be plugged into a socket in the cupboard.     

 

[Tom M]

Hi both, 

Thanks for your help so far. It appears the isolation switch is actually isolating the hob, but not the oven. The hob has its own fuse in the consumer unit, however nothing specific for the oven. I’ve looked in cupboards nearby and cannot locate a switch for the oven. Is this kind of set up common? Or should the oven also have an isolator?

 

[roys]

Quite common for ovens to be fed of the ring circuit (sockets), usually you can get access to this socket, usually it is mounted onto the side of one of the kitchen base units behind lots of plates and bowls. It may also be behind a removal panel on the back of the base unit to get access to the socket, of course the kitchen fitter might not have cut this access panel into the pack of the unit. Or you might only gain access to the socket for the oven if you remove the oven, the last two are not ideal as you don’t have an easy means of isolation.

Just thought of another option, there may be a socket under the kick plate in front of the oven, remove the kick plate and see if there is a socket on the floor.

 

[Murdoch]

Hi both, 

Thanks for your help so far. It appears the isolation switch is actually isolating the hob, but not the oven. The hob has its own fuse in the consumer unit, however nothing specific for the oven. I’ve looked in cupboards nearby and cannot locate a switch for the oven. Is this kind of set up common? Or should the oven also have an isolator?

Don't trust the labels on the fuseboard .

What happens if you turn off the Hob MCB?

 

[Doc Hudson]

Hi both, 

Thanks for your help so far. It appears the isolation switch is actually isolating the hob, but not the oven. The hob has its own fuse in the consumer unit, however nothing specific for the oven. I’ve looked in cupboards nearby and cannot locate a switch for the oven. Is this kind of set up common? Or should the oven also have an isolator?

All fixed appliances should have some form of local, accessible isolation. As 99.9% of appliance instructions typically say you should turn the power off, during routine maintenance & cleaning. Do you know who fitted the kitchen? As it is worth remembering that builders and kitchen fitters have a long history of leaving some very dubious wiring arrangements in kitchens that they claimed to be able to "Include doing the electrics in with the price".  Although it appears to work to the homeowner, some wiring can be poor design and/or a bit inconvenient, whilst others are positively dangerous. Don't assume everything has been done correctly just because a kitchen has some nice new cupboards and worktops.

Doc H.

 

[Evans Electric]

Just repeat what the Doc says above  ....  any appliance should have a  local isolator and it should be accessible .   Many kitchen fitters decide they are also electricians  and do their own thing unfortunately .  

Follow what Roys said also , check behind kickboard etc  .

An electrician may be able to re-configure  it and use the existing cooker switch  . 

 

[BorisJ]

Just repeat what the Doc says above  ....  any appliance should have a  local isolator and it should be accessible .

Actually this is not true. Local isolation is not required. It is usually fitted however. Isolation can be achieved when required at the CU.

as I always set the oven and hob settings to off, as well using the isolator switch, to power off.

Why? You don't need to do this and if you do with many ovens you will loose the clock settigs.

 

[Murdoch]

Actually this is not true. Local isolation is not required. It is usually fitted however. Isolation can be achieved when required at the CU.

Why? You don't need to do this and if you do with many ovens you will loose the clock settigs.

However that is normally only single pole isolation .......... so not ideal.

 

[Evans Electric]

Actually this is not true. Local isolation is not required. It is usually fitted however. Isolation can be achieved when required at the CU.

As far as I know Boris local isolation IS required ,  it always has been  .....unless its been dumped in the 18th .